The primary aim of root canal treatment of teeth with apical periodontitis is to eliminate the microbial load from the root canal system and promote periapical healing. Meticulous mechanical debridement of the root canal system significantly reduces the bacterial load and is considered important in canal disinfection. However, complete elimination of all microorganisms is challenging, as viable bacteria potentially remain on the dentin walls and inside dentinal tubules, both in planktonic forms and biofilms. About 35% of the root canal area is left untouched when conventional rotary and hand instruments are used. Therefore, disinfection with irrigation solutions during root-canal treatment and thereafter obturation of the root canal are important factors to reduce the amount and growth of residual bacteria.

Surface modifications in the nanoscale regime have shown promising potential in the combat against bacterial adhesion and colonization of surfaces. However, detailed knowledge of how the bacteria–substrate interactions occur is still limited.

Leakage of unpolymerized methacrylate monomers after placement of methacrylate-containing polymeric dental materials leads to human exposure. Based on studies using murine macrophages and LPS from Escherichia coli (E. coli), dental monomers like 2-hydroxyethyl methacrylate (HEMA) are known to inhibit lipopolysaccharide (LPS) induced cytokine release.

The results of this study show that CH-MA (CH-MA) may be incorporated into a composite and into an adhesive to reduce biofilm formation on their surfaces. The mechanical properties of the composite were challenged, but flexural strength measurements still met the requirement set in ISO 4049, whereas no differences were observed for the bonding properties of the adhesives.

The results of this study show that methacrylated chitosan (CH-MA) may be incorporated into a composite and into an adhesive to reduce biofilm formation on their surfaces. The mechanical properties of the composite were challenged, but flexural strength measurements still met the requirement set in ISO 4049, whereas no differences were observed for the bonding properties of the adhesives.